function y = sq1(x)
%  Scaled Quadratic SQ1   
%x0=[1,2,...,n]...  
%fmin=n/2,m=20
%Author:shi yangyang
%n=200;
n=length(x);
f=0;
for i=1:n
    f=f+x(i)*x(i);
end
y=f/2.0;